Global environmental assessments are widely considered to play a prominent role in environmental governance. However, they are also criticised for a lack of effectiveness in informing policy and decision-making. In response, GEAs have adopted a number of strategies to bolster their effectiveness, including by orienting themselves towards solutions (solution-orientation), increasing the diversity of included experts (participation), and producing more targeted assessments (contextualisation). In this article, we analyse these strategies as attempts to be effective for multiple audiences while also identifying the limitations of these strategies. Based on this analysis, we propose to conceive of GEAs as processes that are able to empower diverse actors – ranging from diplomats in international negotiations to civil society activists, or indigenous and local knowledge holders – to act towards socio-environmental objectives. Seen in this light, the effectiveness of GEAs can be improved by reflecting on which actors can benefit from assessments and how assessments can contribute to their empowerment. This strategy goes beyond current proposals that aim to strengthen the authority of assessments by boosting the scientific quality and credibility of the reports. Indeed, it complements them with an explicitly political perspective. Using examples of empowerment in different phases of GEA production and use, we argue that this reconceptualisation of effectiveness requires assessments to reflect a diversity of problem and solution frames, thereby creating entry points for the empowerment of a broad range of actors. We conclude by providing three illustrative ideas to improve effectiveness for the design and execution of assessments.